The MARATHON 70 achieves revolutionary head safety through the use of BRITAX SafeCell Technology, Integrated Steel Bars, and Versa-Tether that work together to minimize head excursion and reduce the risk of head injury during a frontal impact. Rear-Facing 5- 40 lbs, a standing height of 49 inches or less and seated shoulder height of 9-16.75 inches. Forward-Facing 1 year & 20, up to 70 lbs, a standing height of 49 inches or less and a seat shoulder height of 12-16.75 inches. SafeCell Technologyfeatures SafeCells designed to compress in a crash, significantly lowering the center of gravity and counteracting the forward rotation of the child seat which normally propels the child toward the front seat Integrated Steel Bars strengthen the connection to the vehicle and reduce forward flexing of the child seat during a crash Patented, Energy-Absorbing Versa-Tetherfeatures a staged-release tether webbing to slow the forward movement, reducing the crash forces reaching the child, and a two-point attachment to minimize forward rotation while anchoring the top of the child seat 360 Degree Protection Features Side Impact Protection comprised of deep side walls lined with energy-absorbing EPP foam distributes crash forces, shields from vehicle intrusion, and contains the head, neck and body Tangle-Free, Five-Point Harness distributes crash forces across the strongest parts of the body and provides a secure fit Harness Ultra Guard System (HUGS) provides resistance to forward movement in the event of a crash Superior Fit and Comfort Features 70-pound Weight Capacity for safety and comfort as your child grows Rear and Forward Facing Recline for child comfort and positioning High Density Comfort Foam provides an extra layer of padding to gently cushion your child Plush, Easy-Remove Cover with matching comfort pads and infant body pillow to provide extra comfort and easy cleaning without disassembling or uninstalling the child seat Two Buckle Positions for your growing child Infant Positioning Insert may be necessary for small infants to achieve a snug fit of the harness around your child (sold separately) Superior Ease-of-Use Features Quick-Adjust Harness repositions the harness shoulder height without disassembling the harness straps Premium Lower LATCH Connectors for a quick and simple installation featuring a push button for easy release Built-in Lock-Offs ensure a snug lap and shoulder belt installation with minimal effort Anti-Slip, Contoured Base grips and protects the vehicle seat while offering optimum vehicle fit Convenient Harness Holders keep harness straps out of the way when placing your child in the car seat. *We provide instructions but will not be available to install or help, due to liability/insurance reasons*